Performance of a Highly Granular Scintillator-SiPM Based Hadron Calorimeter Prototype in Strong Magnetic Fields

Within the CALICE collaboration, several concepts for the hadronic calorimeter of a future linear collider detector are studied. After having demonstrated the capabilities of the measurement methods in "physics prototypes", the focus now lies on improving their implementation in "engineering prototypes", that are scalable to the full linear collider detector. The Analog Hadron Calorimeter (AHCAL) concept is a sampling calorimeter of tungsten or steel absorber plates and plastic scintillator tiles read out by silicon photomultipliers (SiPMs) as active material. The front-end chips are integrated into the active layers of the calorimeter and are designed for minimizing power consumption by rapidly cycling the power according to the beam structure of a linear accelerator. The versatile electronics allows the prototype to be equipped with different types of scintillator tiles and SiPMs. A prototype with ~2200 channels, equipped with several types of scintillator tiles and SiPMs, was tested with muons and electrons in a 1.5 T magnet at the CERN SPS in May 2017 to establish the operational stability with power pulsing and the overall detector performance in a magnetic field.